The objective of this proposal is to develop reconstituted skin that can form new hairs from dissociated stem cells. Progress has been made in producing hair follicles using dissociated multi-potential dermal and epidermal stem cells. However, couple gaps need to be filled before significant progress in clinical applications can be made. Recently, we have improved significantly the previous assays by Lichti and Stenn into a simpler hair forming assay with clinically proper appearance and potential for a high throughput assay. Our general hypothesis is that multi-potent skin stem cells can be generated by molecular reprogramming, and that arrangement and patterning of hair primordia can be regulated by environmental conditions. With the newly developed planar hair forming procedure, we are able to apply our expertise in feather pattern formation to regulate the number and size of hair primordia. We will also apply our recent experience on macro-environment regulation of hair stem cells to improve the efficiency of hair formation. Recent success of molecular re-programmig in other organs has inspired excitement. This simple assay will allow us to do high throughput analyses to identify molecules or combinations of molecules important to reprogram adult skin cells into hair forming dermal and epidermal cells. The development of this technology will bring new hope to those who suffer from severe wounds and alopecia.